Antibodies: The basis of the humoral response

This 150kDa, Y-shaped molecule plays many roles in immunity. An antibody is able to act as a molecular flag by binding to a specific structure on a given pathogen (the so called antigen) in order to recruit other immune cells which may finally destroy the infecting microorganism. By contrast, neutralizing antibodies(nAbs) are known to prevent viral entry into the host cell by interfering with infection mechanisms. Antibodies are secreted by B cells and plasma cells (terminally differentiated B cells). They are important for both serological diagnosis of infections such as HIV, and for the treatment of many human diseases. In the last years, the monoclonal antibody industry exploded and many recombinant antibodies are today available as validated drugs.